Systems and methods for dynamic range enhancement using an open-loop modulator in parallel with a closed-loop modulator
US9503027B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 27, 2014 |
| Grant date | Nov 22, 2016 |
| Priority date | — |
| Expiry date | Oct 27, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/432
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An integrated circuit may have two signal paths: an open-loop modulator (which may comprise a digital-input Class-D amplifier) and a closed-loop modulator (which may comprise an analog-input Class-D amplifier). A control subsystem may be capable of selecting either of the open-loop modulator or the closed-loop modulator as a selected path based on one or more characteristics (e.g., signal magnitude) of an input audio signal. For example, for higher-magnitude signals, the closed-loop modulator may be selected while the open-loop modulator may be selected for lower-magnitude signals. In some instances, when the open-loop modulator is selected as the selected path, the closed-loop modulator may power off, which may reduce power consumption. In addition, one or more techniques may be applied to reduce or eliminate user-perceptible audio artifacts caused by switching between the open-loop modulator and the closed-loop modulator, and vice versa.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.